On the vectorial calibration of a vibrating sample magnetometer for thin film measurements

A calibration method for the biaxial vector Vibrating Sample Magnetometer (VSM) is proposed to reduce the so-called `cross talk’ error, often observed during angular measurements on magnetic thin films. The coil system of the biaxial vector VSM consists of two sets of coils, one for each of the two co-ordinate axes. The method takes into account that each coil set is sensitive to all components of the magnetisation vector and moreover that the sensitivity to the components parallel and perpendicular to the film plane can be different. A correction for demagnetisation should be used to compensate the fact that the sample used for the calibration cannot be fully saturated with an applied field at angles close to the normal of the film plane. Curve-fitting on the sensitivity curves is used to reduce noise. These procedures result in a calibration which reduces the cross talk by a factor 4–8 depending on the coil configuration and the size and shape of the samples used.